Improvement and evaluation of daily global solar radiation decomposition models using meteorological parameters: A case study for Turkey

Abstract
In this study, some of the commonly used daily global solar radiation decomposition models are improved by considering ambient temperature, relative humidity, and air pressure to estimate hourly global solar irradiance from measured daily global solar radiation in Eskişehir, Turkey. Accordingly, the identified functions of the considered parameters are integrated into the selected daily global solar radiation decomposition models. The accuracy of the improved models is evaluated based on the measured monthly average hourly global solar irradiance values. In addition, the monthly average power values provided by the original and improved models are compared with the measured power output values. The results indicate that the improved models have significantly higher performance in the accuracy of both global solar radiation estimation and power output forecasting in a specific time interval. Therefore, the proposed methodology can be used to improve any global solar radiation decomposition model based on locally measured data for different regions.